Novel algorithm to reduce the complexity of quarter-pixel motion estimation
Priyanka Gupta, Ramkishor Korada · Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE · 2004
Quarter pixel precision motion compensation became a common tool in advanced video compression standards such as MPEG-4 Advanced Simple Profile (ASP), H.264 because of its ability to represent motion more accurately than half pixel precision. MPEG-4 ASP uses 8-tap symmetric filter in finding interpolated sample values at half pixel resolution in quarter pixel precision motion compensation. This new tool increases the computational complexity of the fractional pixel motion estimation on the encoder side compared to the integer pixel motion estimation, in terms of computation of interpolated sample values as well as number of fractional pixel search points. This paper presents a way to reduce the complexity of quarter pixel motion estimation by reducing the filter tap length. Reduction in computation complexity and variation in PSNR values with different filters are presented.